Vegetation restoration is associated with increasing forest width

New Forests - Monitoring and assessment reveal important information about restoration areas and can also be useful for understanding ecological processes such as succession and species-area...     

Formation of a Reservoir of Sperm in the Oviduct

A reservoir of sperm in the initial segment of the oviduct has been found in several species of domestic and laboratory mammals. Evidently, the reservoir serves to ensure successful fertilization by providing the appropriate number of sperm in the appropriate physiological state for fertilizing oocytes soon after they enter the oviduct. Recent evidence indicates that sperm are trapped in the reservoir by binding to specific carbohydrate moieties on the surface of the mucosal epithelium of the oviduct. A bovine seminal plasma protein has been identified that associates with sperm and confers on them the capacity to bind to the carbohydrate moiety.     

Modified Pollard transects for assessing tropical butterfly abundance and diversity

This paper introduces and discusses the consistency and effectiveness of an inexpensive modification of Pollard transects for assessing the diversity and abundance of tropical butterfly communities in two national parks in Rio de Janeiro, Brazil. To measure butterfly abundance, students walked simultaneous timed transects at the interface of forest and cleared areas. They either counted the number of individuals observed or tabulated the number of specimens collected with nets. After a short training period, the number of butterflies observed or collected on simultaneous transects was statistically indistinguishable among student groups, and there was a significant positive correlation between observation counts and collected number of individuals. As a measure of species richness, the number of butterfly species sampled on each simultaneous transect was tabulated and did not differ statistically. To measure diversity, alpha of the logseries model was calculated for each collected sample, and statistical fit to a logseries model was determined. Although virtually all daily samples and the year's accumulated sample at one park fit the logseries model, about 35% of the daily samples and the entire year's sample did not fit at the other park. Despite these differences between the two parks, values for alpha from daily samples at both parks varied similarly (from 15 to 50 in almost all cases), and values from the entire year's samples were statistically indistinguishable. The repeatability of results among novices, such as students, suggests that timed transects have great promise for furthering our understanding of butterfly community demographics.     

Estimating the level of disease risk and biosecurity on commercial poultry farms in New Zealand

ABSTRACT

Aims: To collect baseline data on the contact risk pathways and biosecurity practices of commercial poultry farms in New Zealand, investigate the relationship between the farm-level disease contact risks and biosecurity practices, and identify important poultry health concerns of producers.

Methods: A cross-sectional survey of all registered New Zealand commercial poultry operations was conducted in 2016 collecting information on farm demographics, biosecurity practices, and contact risk pathways. Survey responses were used to generate an unweighted subjective disease risk score based on eight risk criteria and a subjective biosecurity score based on the frequency with which producers reported implementing seven biosecurity measures. Producer opinions towards poultry health issues were also determined.

Results: Responses to the survey response were obtained from 120/414 (29.0%) producers, including 57/157 (36.3%) broiler, 33/169 (19.5%) layer, 24/55 (44%) breeder, and 6/32 (19%) other poultry production types. Median disease risk scores differed between production types (p?<?0.001) and were lowest for breeder enterprises. The greatest risk for layer and broiler enterprises was from the potential movement of employees between sheds, and for breeder enterprises was the on- and off-farm movement of goods and services. Median biosecurity scores also differed between production types (p?<?0.001), and were highest for breeder and broiler enterprises. Across all sectors there was no statistical correlation between biosecurity scores and disease risk scores. Producers showed a high level of concern over effectively managing biosecurity measures.

Conclusions: The uptake of biosecurity measures in the commercial poultry farms surveyed was highly variable, with some having very low scores despite significant potential disease contact risks. This may be related to the low prevalence or absence of many important infectious poultry diseases in New Zealand leading farmers to believe there is a limited need to maintain good biosecurity as well as farmer uncertainty around the efficacy of different biosecurity measures. Further research is needed to understand barriers towards biosecurity adoption including evaluating the cost-effectiveness of biosecurity interventions.     

Nitric oxide impacts bovine sperm capacitation in a cGMP‐dependent and cGMP‐independent manner

We aimed to elucidate whether NO acts in in vitro sperm capacitation in bovine via cGMP/PKG1 pathway. For this, cryopreserved bovine sperm were capacitated in vitro with 20 µg/ml heparin (Control) plus treatments: 1 mM L‐arginine (L‐arg, NO precursor), 50 µM Rp‐8‐Bromo‐β‐phenyl‐1,N²‐ethenoguanosine‐3′,5′‐cyclic monophosphorothioate (Rp‐8‐Br‐cGMPS, selective inhibitor of the binding site for cGMP in PKG1), 1 mM 2‐Phenyl‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl 3‐oxide (PTIO, NO scavenger), and the combinations of L‐arg + RP‐8‐Br‐cGMPS and L‐arg + PTIO. Sperm motility and vigour were determined by phase‐contrast microscopy, capacitation status by chlortetracycline staining, and the intracellular concentration of cGMP was measured by ELISA. Data were subjected to analysis of variance and means compared with SNK test at 5% probability. Motility and vigour were lower in sperm treated with PTIO when compared to Control and other treatments (p < .05). The L‐arg treatment showed the highest percentage of capacitated sperm when compared to the Control and other treatments (Rp‐8‐Br‐cGMPS, L‐arg + Rp‐8‐Br‐cGMPS and PTIO) (69.8 ± 3.4%, 51.2 ± 3.0, 51.1 ± 2.1, 51.2 ± 3.0 and 45.5 ± 2.7, respectively) (p < .05). The capacitation ratio (%) was lower in treatments with Rp‐8‐Br‐cGMPS, L‐arg + Rp‐8‐Br‐cGMPS and PTIO, respectively (p < .05). Lastly, cGMP concentration (pmol/ml) was lower in PTIO and L‐arg + PTIO (1.3 ± 0.3 and 1.6 ± 0.4) and was higher in Rp‐8‐Br‐cGMPS and L‐arg + Rp‐8‐Br‐cGMPS (3.7 ± 0.4 and 4.0 ± 0.5) treatments. We showed that during in vitro capacitation of cattle: (a) NO influences sperm motility and vigour; (b) NO is associated with cGMP synthesis through two independent pathways and (c) the cGMP/PKG1 pathway has a partial role in sperm capacitation and does not involve the L‐arg/NO.     

The effects of osmolality on sperm quality in <Emphasis Type="Italic">Jenynsia multidentata</Emphasis> (Cyprinodontiformes: Anablepidae)

Sperm quality tests on fish are classically used for evaluating cryopreservation procedures, and they are also promising to assess aquatic toxicity and biomarkers of xenobiotic effects on reproduction. Osmotic shock from the storage medium is one of the main factors affecting sperm quality during evaluation. Thus, the objective of this study was to evaluate the effects of different osmolalities (240–460 mOsm/kg) for at least 4 days on the sperm quality parameters of the viviparous fish Jenynsia multidentata. The level of significance was (P < 0.05). The plasma osmolality of J. multidentata is 326 ± 3.9 mOsm/kg. The motility of fresh semen was higher in osmolalities of 280 and 300 mOsm/kg but did not differ between osmolalities from 240 to 320 mOsm/kg. Above 380 mOsm/kg, the motility observed was 0 %. Over the time period studied motility increased with increasing osmolality, and the most constant and long-lasting rates were between 300 and 320 mOsm/kg. On the 4th day of evaluation, higher membrane integrity rates were observed between 280 and 360 mOsm/kg, higher mitochondrial membrane potential was observed between 300 and 460 mOsm/kg, and higher DNA integrity rates were observed between 260 and 380 mOsm/kg. Moreover, osmolalities ≥460 and ≤240 resulted in the lowest motility and DNA integrity levels. Over 4 days, the plasma membrane integrity was significantly lower at ≤260 and ≥400 mOsm/kg, and the mitochondrial membrane potential was significantly lower only in osmolalities ≤240 mOsm/kg. Therefore, we conclude that for sperm quality preservation in J. multidentata, an osmolality of 300–320 mOsm/kg of the most suitable diluent is necessary. Furthermore, we conclude that the storage of sperm in a hyposmotic (<260 mOsm/kg) or hyperosmotic (>400 mOsm/kg) solution affects not only motility but also other sperm quality parameters.